Holliday Jeffrey J, Reidy Patrick F, Beckman Mary E, Edwards Jan
J Speech Lang Hear Res. 2015 Jun;58(3):622-37. doi: 10.1044/2015_JSLHR-S-14-0090.
Four measures of children's developing robustness of phonological contrast were compared to see how they correlated with age, vocabulary size, and adult listeners' correctness ratings.
Word-initial sibilant fricative productions from eighty-one 2- to 5-year-old children and 20 adults were phonetically transcribed and acoustically analyzed. Four measures of robustness of contrast were calculated for each speaker on the basis of the centroid frequency measured from each fricative token. Productions that were transcribed as correct from different children were then used as stimuli in a perception experiment in which adult listeners rated the goodness of each production.
Results showed that the degree of category overlap, quantified as the percentage of a child's productions whose category could be correctly predicted from the output of a mixed-effects logistic regression model, was the measure that correlated best with listeners' goodness judgments.
Even when children's productions have been transcribed as correct, adult listeners are sensitive to within-category variation quantified by the child's degree of category overlap. Further research is needed to explore the relationship between the age of a child and adults' sensitivity to different types of within-category variation in children's speech.
比较四种衡量儿童语音对比稳健性发展的指标，以了解它们与年龄、词汇量以及成人听众的正确性评分之间的相关性。
对81名2至5岁儿童和20名成人词首擦音的发音进行语音转录和声学分析。根据从每个擦音样本测量的质心频率，为每位说话者计算四种对比稳健性指标。然后，将不同儿童转录为正确的发音用作感知实验的刺激材料，让成人听众对每个发音的优劣进行评分。
结果表明，类别重叠程度（量化为根据混合效应逻辑回归模型的输出能够正确预测儿童发音类别的百分比）是与听众优劣判断相关性最强的指标。
即使儿童的发音被转录为正确，成人听众仍对由儿童类别重叠程度量化的类别内变异敏感。需要进一步研究来探讨儿童年龄与成人对儿童语音中不同类型类别内变异的敏感度之间的关系。
